Caspase-1 activity is required to bypass macrophage apoptosis upon Salmonella infection

Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA, USA.
Nature Chemical Biology (Impact Factor: 13.22). 07/2012; 8(9):745-7. DOI: 10.1038/nchembio.1023
Source: PubMed

ABSTRACT Here we report AWP28, an activity-based probe that can be used to biochemically monitor caspase-1 activation in response to proinflammatory stimuli. Using AWP28, we show that apoptosis is triggered upon Salmonella enterica var. Typhimurium infection in primary mouse bone marrow macrophages lacking caspase-1. Furthermore, we report that upon Salmonella infection, inflammasome-mediated caspase-1 activity is required to bypass apoptosis in favor of proinflammatory pyroptotic cell death.

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